Development of gluconeogenesis in neonatal pig liver
Helmrath, T.A.; Bieber, L.L.
American Journal of Physiology 227(6): 1306-1313
1974
ISSN/ISBN: 0002-9513 PMID: 4440775 Document Number: 78445
Yorkshire X Hampshire pigs 1, 5 or 24 days old were fasted for 24 h, but given water, and then killed. Specific activities of soluble and mitochondrial phosphoenolpyruvate carboxykinase, mitochondrial pyruvate carboxylase and gluconeogenic rates in vitro from lactate were estimated in liver. In all the groups soluble phosphoenolpyruvate carboxykinase specific activities were similar, while mitochondrial phosphoenolpyruvate carboxykinase and pyruvate carboxylase specific activities increased significantly in the pigs 5 and 24 days old. Liver slices from the pigs 1 day old generated glucose from lactate at one-third the rate at age 24 days. Although infusion by vein of oleate in pigs 1 day old raised their plasma fatty acids, their liver tissue showed no difference in gluconeogenic rates from lactate in vitro or in enzyme specific activities. Oleate added to the incubation media of liver slices from the pigs 5 days old had no effect on the gluconeogenic rates from alanine or lactate.